Electrical or Mechanical Fan

[IanDaddy]

I have done some reading lately and found the following,My E46 325i M54 comes with 2 fans (electrical aux fan and a mechanical fan with clutch)Saw a few E46 318i N42 - 1 Electrical puller fan onlyFriend's E60 M54 - 1 Electrical puller fan onlyFriend's E90 320i - 1 Electrical puller fan onlyRead that E46 MT comes with 1 Electrical puller only.The mechanical fan , once engaged it is very noisy as it spins along with the engine RPM. When you rev from 1000 to 3000 rpm it sounds like an airplane taking off. I read that some with Steptronics have replaced the aux fan and mech fan clutch with just one electrical puller fan, no problem. It is plug and play , the connector simply plugs into the aux fan harness.I think electrical fan is superior because first it spins at variable rate but independent of the rpm (unless you like the engine roar). It also free up the load on the engine ( you can feel when the fan clutch is engaged when you rev from stand-still). Any chance the sifus here know the CFM (cubic feet / minute, I think) ratings of the mech and electrical fans ?What are the experience of the OM and forumers ?

 

[V-Man]

You can decide from here>> http://www.peachparts.com/shopforum/showthread.php?t=234663

Good luck.

 

[tropos_net]

well as far as loading is concern, its basically shifting the load from the water pump pulley (mech fan) and into the alternator as a electrical load (elect fan). of course each of that load will still hit the engine in the end but the user experience may differ. so this can be viewed as converting the mech. load into electrical load. each will have ups and downs.

 

[IanDaddy]

Tropos, agree with you on the load thing. Wonder which one is more energy efficient ?

 

[tropos_net]

well put it this way, all those who had done this conversion had claimed quicker acceleration. maybe that can be the driving factor as i have not seen that electr fan failure either tbh. the last i checked the fan assembly with the motor/blades cost 880rm

 

[IanDaddy]

Tropos, thanks for your thoughts.

I think the pros of electrical fans are they speed is totally independent of engine. Imagine when idling in traffic jam, the e-fan can be on or off or at low or high speed while the mech-fan is either free-wheeling or engaged and run proportional to the rpm.
I think acceleration feels better because mech-fan is directly loaded to the engine and the inertia thingy. The torque of the electrical motor is instantaneous I think.

I think newer cars mostly have e-fans.

 

[IanDaddy]

Tropos, so you actually considered the mod ? what was your driving factor for the consideration?

 

[tropos_net]

well yes, i would feel safer with electrical motor for a different reason....have a look at the gap between the plastic fan (of the mech fan setup) and the plastic cowling surrounding it. that gap starts to be nearer on one end as the engine mounting flexes with age. they come into contact then BANG! so have to monitor very closely.

 

[IanDaddy]

Tropos , your concern is well founded. I have this experience where the water pump bearing failed suddenly without notice. Since the fan clutch is mounted on the water pump pulley when the bearing failed the whole pulley went wobbly and the fan actually hit the fan shroud and part of the engine. Luckily, I was right in front of my friend's workshop. Even the water pump pulley was slightly damaged, replaced too.

I feel that fan blade , if for some reasons is not well balanced it can put uneven load on the water pump bearing causing pre-mature wear. The thought of this failure always bother me as I may not get lucky next time and may get stranded, hence my search for some solutions.

 

[feisaldzul]

i am running the electric fan on my e39 for some time now.
two thumbs up.
definitely better pick up with no more of that airplane take off sound which bugged me real bad.

when i was on the clutch fan, i had the experience of my fan blowing up into pieces at least 3x. dented the hood.
drove the car fan-less from Penang to KL but at nite.

 

[bmw7833]

i am running the electric fan on my e39 for some time now.
two thumbs up.
definitely better pick up with no more of that airplane take off sound which bugged me real bad.

when i was on the clutch fan, i had the experience of my fan blowing up into pieces at least 3x. dented the hood.
drove the car fan-less from Penang to KL but at nite.

Yours is powderfull car so need powderfull fan also ma.

 

[bimmerholic]

i am running the electric fan on my e39 for some time now.
two thumbs up.
definitely better pick up with no more of that airplane take off sound which bugged me real bad.

when i was on the clutch fan, i had the experience of my fan blowing up into pieces at least 3x. dented the hood.
drove the car fan-less from Penang to KL but at nite.

Bro, is there any need to upgrade the Alternator to higher AMPs? - since the additional of an elect fan is an extra load.
Did you also change your radiator or you maintained your original radiator when fitting in the new elect fan? Cuz i've seen some manufacturers make the electric fan and the aluminium radiator as one set. Is that a better option?

 

[IanDaddy]

Bimmerholic, I have the similar thought because of the extra electrical load but since most of the mod takes out the electrical aux fan too , it may be ok provided the electrical fan power rating is the same to what is taken off (the aux fan).

The sound bugs me like hell , not to mention blown up fan clutch.

 

[feisaldzul]

no changes to alternator or radiator. same old same old. no issue. more than 1.5 years I think.

 

[Galaxy7]

what is the price for conversion to electical fan?

 

[tropos_net]

what is the price for conversion to electical fan?

the elect. fan motor housing complete assy (replacement for mech fan) costs 880rm from BA. there might be some minor wiring mod needed depending on which E46 model. no need to worry abt ampere rating of the alternator (also confirmed by feisal) because the fan runs only when needed (not ON all the time). if there is no AUX fan fitted in FRONT of radiator in yr model, then its wise to add that too together with this mod.